1. Field of the Invention
The present invention relates to an ultrasound observation apparatus, and in particular, to an ultrasound observation apparatus that can calculate temporal variation of luminance in a region of interest.
2. Description of the Related Art
An ultrasound observation apparatus has been widely used in a medical field or other fields. The ultrasound observation apparatus transmits and receives ultrasound to/from a subject to generate an ultrasound image that indicates acoustic characteristics inside the subject, and uses the ultrasound image in inspection and diagnosis of the subject.
The ultrasound observation apparatus used in the medical field or other fields includes an ultrasound probe that is capable of transmitting and receiving ultrasound to/from the subject, and generates a B-mode image that is a cross-sectional image of the subject. The B-mode image is obtained through scanning of a predetermined scanning plane with an ultrasound beam.
For example, Japanese Patent No. 4801229 discloses an ultrasound observation apparatus that acquires volume data of a B-mode image, and then calculates correlation in all scanning planes to constantly display an optimum scanning plane (having the highest correlation) in order for continuous favorable observation of a treatment using treatment instruments without deviation from the scanning plane.
Also, such an ultrasound observation apparatus uses TIC (time intensity curve) analysis as an objective diagnostic approach using an ultrasound contrast agent. In the TIC analysis, a region of interest (ROI) for TIC analysis is set to a region of interest in the scanning plane, and temporal variation of contrast luminance in the ROI is calculated.
For example, Japanese Patent Application Laid-Open Publication No. 2011-254963 discloses an ultrasound diagnostic apparatus that generates luminance time curves of at least one analysis region with, as a scanned region, a two-dimensional region or a three-dimensional region including a predetermined site of a subject medicated with a contrast agent, then analyzes a retention time period of the contrast agent in the analysis region to display different color phase that is assigned dependently on the retention time period.